Roller track apparatus



. Aug. 9, 1966 K. A. AHO v 3,255,450

ROLLER TRACK APPARATUS Filed oct. 17, 1965 United States Patent ODelaware Filed ct. 17, 1963, Ser. No. 316,914 2 Claims. (Cl. 308-6) Thisinvention relates to roller track apparatus and more particularly totapered roller track apparatus.

Generally, theroller track apparatus of this invention supports a pairof members for movement relative to each other, and includes a pair orroller tracks on one of the members and sets of tapered roller unitsrotatably mounted on the other member and received within respectiveroller tracks. Means are :also provided for wedgingly engaging therollers with the tracks to take up lash in directions transverse of thedirection of relative movement between the members. up means have beenlimited to only partial take-up, past which the rollers would tend tobind or skid within the tracks rather than rol-l thereover. However, thelash take-up means of this invention is operable to fully take up lashbetween the members but yet will not bind or cause skidding of therollers, nor in any way restrain the members from their normal relativemovement.

The primary object of this invention is to provide new and improvedroller track apparatus. Another object of this invention is to providenew and improved roller track apparatus including lash take-up means. Afurther object of this invention is to provide new yand improved rollertrack apparatus including :lash take-up means operable to take up lashwithout causing binding or skidding between the roller and trackelements of the apparatus.

These and other objects Iand advantages will be readily apparent fromthe following specification and drawings wherein:

FIGURE 1 is a plan view of roller track apparatus according to thisinvention;

FIGURE 2 is an enlarged sectional view taken gener- `ally along theplane indicated by line 2 2 of FIGURE 1; and j FIGURE 3 is an explodedperspective view.

Referring now to FIGURES 1 and 2, reference characters and 12 indicate apair of upper and lower members which are to be supported for movementrelative to each other. Member 10 has secured thereto by screws 18 apair of like spaced elongated roller tracks 14 and 16 provided withr-oller recesses or channels 20 and 22 opening inwardly of mem-ber 10.The channels 20 and 22 are of generally frusto-conical or wedge-shapedcross section and include oppositely inclined support or guide surfaces24 and 26, each upper surface 26 extending inwardly beyond the opposite:lower surface 24. Spaced pairs of rol-ler units 2S 'and 30 are mountedon member 12 adjacent opposite edges thereof :and are respectivelyreceived in roller tracks 14 and 16.

As seen best in FIGURE 2, each roller unit 30 includes a roller shaft orpin 32 secured in a block 34 which is welded to member 12. Inner andouter rollers 36 and 38 are journaled on shaft 32, with a thrust washer40 being interposed between rollers 36 and 38, and a pair of thrustwashers 42 being interposed between roller 38 and block 34. Roller 38has a tapered roller surface 39 complementary to surface 26 of theroller track 4for full rolling engagement therewith, and roller 36 has atapered roller surface 37 complementary to surface 24 for full rollingengagement therewith. The diameters 0f rollers 36 and 38 arerespectively smaller and larger than the distance between the planes ofsurfaces 24 and 26 at the locations at which the rollers complementarilyengage the respec- In the past, such lash take- 3,265,450 PatentedAugust 9, 1966 tive surfaces, and the axes of shafts 32 are somewhatoffset from Ihorizontal planes bisecting the respective chanrice nels 20and 22 and, in the embodiment shown, generally.

parallel to such planes. This, together with the projection of surface26 beyond surface 24, locates the rollers so that roller 36 engages onlysurface 24, and roller 38 engages only surface 26.

The roller units 28 are identical to roller -units 30 with the exceptionof lash adjusting means provided in roller units 28, presently to bedescribed, so that all four roller units engage in their respectiveroller tracks in the abovedescribed manner and rollably support themembers 10 and 12 for relative movement in the direction of elongationof the roller tracks. A stop member 44 mounted on member 12 projectsinto a central aperture 46 of member 10 for engagement with oppositeedges of the aperture to limit relative movement between the members.

Lash take-up means for effecting full engagement of the roller sur-facesof each roller 36 :and 38 of all four roller unit-s provided in each ofthe roller units 28 include a portion 48 of shaft 32 threadedly receivedin a tapped bore 50 in block 34 rather than fixed therein as in the.roller units 30. A thrust washer 54 is interposed between the shoulderof threaded portion 48 and roller 38.

The inner projecting end of portion 48 is slotted or otherwise adaptedfor use with a screw driver or other common tool to axially yadjust theshaft and the rollers 36 and 38 relative to block 24 so 4as to fullywedgingly engage the tapered roller surfaces 37 and 39 of each rollerunit 28 with the respective roller track support surface. Upon suchwedging engagement of the roller units 28, a slight lateral shift ofmembers 10 and 12 will result so that both sets of roller units 28 and30 are tightly 6ngaged to take up lash in both roller tracks. A nut 52ifs threaded on the projecting end of portion 48 to engage block 34 andmaintain the selected lash adjustment.

It will be apparent that since each roller of the individual rollerunits is engageable with only one supportsurface of the roller trackrather than both surfaces thereof, .a tight wedging engagement of theroller with that surface to take up lash may be effected withoutcreating the binding frictional couple on opposite sides of the rollerthat has heretofore been the case. Consequently, the rollers 36 and 38will Ialways freely roll in the tracks and smooth operation of theapparatus is ensured.

Thus new and improved roller track apparatus is provided.

I claim:

1. The combination comprising, a pair of relatively movable members, anelongated roller track on one of said members having a pair of supportsurfaces forming a roller channel, said surfaces -being formed alongintersecting planes inclined oppositely relative to a plane therebetweenbisecting said channel, first roller means rotatably mounted on theother of said members within said channel about an axis lying outsidesaid bisecting plane :and having a tapered roller surface complementaryto one of said support surfaces for full flush rolling engagementexclusively therewith, second roller means rotatably mounted on saidother member within said channel coaxially with said first roller meansand having a tapered roller surface complementary to the other of saidsupport surfaces for full flush rolling engagement exclusivelytherewith, and means for axially adjusting said first and second rollermeans relative to to said mem- Ibers to wedgingly engage said first andsecond roller means with respective support surfaces to provide fornonskid lash take-up between said members.

2. Roller track apparatus as recited in claim 1, wherein said axis isparallel to said bisecting plane, one of said support surfaces extendingbeyond the other of said support surfaces, and wherein said rollersurfaces are discon- 9 ..a 4f coptmpously 'tapered whereby sa1d roller Ineans engage FOREIGN PATENTS excluswely w1th the support surfacerespectlve to each.

830,270 1/1952 Germany. References Cited by the Examiner 834,161 2/1952Germany.

5 44 UE?? TATES PATENTS 312 34 DAVID J. WILLIAMOWSKY, PrimaryExammer.844, 7 I 9 autier 2 2,258,267 10/1941 shimer 30s- 231 DON A- WAITEExamine 187-95 X L. L. JOHNSON, Assistant Examiner.

3,061,045 10/1962 Gunning

1. THE COMBINATION COMPRISING A PAIR OF RELATIVELY MOVABLE MEMBERS, ANELONGATED ROLLER TRACK ON ONE OF SAID MEMBERS HAVING A PAIR OF SUPPORTSURFACES FORMING A ROLLER CHANNEL, SAID SURFACES BEING FORMED ALONGINTERSECTING PLANES INCLINED OPPOSITELY RELATIVE TO A PLANE THEREBETWEENBISECTING SAID CHANNEL, FIRST ROLLER MEANS ROTATABLY MOUNTED ON THEOTHER OF SAID MEMBERS WITHIN SAID CHANNEL ABOUT AN AXIS LYING OUTSIDESAID BISECTING PLANE AND HAVING A TAPERED ROLLER SURFACE COMPLEMENTARYTO ONE OF SAID SUPPORT SURFACES FOR FULL FLUSH ROLLING ENGAGEMENTEXCLUSIVELY THEREWITH, SECOND ROLLER MEANS ROTATABLY MOUNTED ON SAIDOTHER MEMBER WITHIN SAID CHANNEL COAXIALLY WITH SAID FIRST ROLLER MEANSAND HAVING A TAPERED ROLLER SURFACE COMPLEMENTARY TO THE OTHER OF SAIDSUPPORT SURFACES FOR FULL FLUSH ROLLING ENGAGEMENT EXCLUSIVELYTHEREWITH, AND MEANS FOR AXIALLY ADJUSTING SAID FIRST AND SECOND ROLLERMEANS RELATIVE TO TO SAID MEMBERS TO WEDGINGLY ENGAGE SAID FIRST ANDSECOND ROLLER MEANS WITH RESPECTIVE SUPPORT SURFACES TO PROVIDE FORNONSKID LASH TAKE-UP BETWEEN SAID MEMBERS.